Leonardo da Vinci designed a rotating organ gun with multiple barrels arranged around a wheel.
The weapon, sometimes called a multi-barrelled gun, placed several small cannon barrels on a frame. The arrangement was intended to allow repeated firing and easier aiming than a single heavy gun. Its nickname comes from the visual resemblance between the rows of barrels and the pipes of a musical organ.
Leonardo included the design among his military-engineering studies in the late fifteenth century. It was not a modern machine gun: the barrels still required separate loading and firing, and the mechanism did not provide continuous automatic fire. The practical rate of fire would also have been limited by smoke, recoil, and the time needed to prepare the weapon.
The design illustrates Leonardo’s interest in solving battlefield problems through repetition and organization. Multiple barrels could increase the number of shots delivered in a short period, while the rotating arrangement helped bring fresh barrels into position.